The present invention relates to an amusement machine of a type wherein a moving luminous mark projected on a screen is shot by a marksmen with a gun which emits a light beam.
In systems of this general type, there are elaborate arrangements wherein a successful shot with a light beam gun at a mark on a screen is indicated by the cancellation of the mark and the projection of a falling mark on the screen. Also, there are systems which incorporate thereinto electronically controlled visual and audio indicators for indicating the hit. However, the electronic circuity which is necessarily required for these systems demands a high degree of complexity, especially when the system is provided with both a target mark projection unit and a separate hit mark projection unit, thereby making the apparatus both too costly and bulky for general entertainment use.
The applicant has overcome many of these problems in his prior U.S. Patent, U.S. Pat. No. 4,052,066 which provides for a home entertainment device of this type with a greatly simplified target projecting means and hit indication means. In that patent, the flight of the target object is indicated by a constant change in the area and configuration of the target through changing the block area of the mark aperture by means of movable shutter members. When the mark is sucessfully hit, the movement of the shutters is ceased and a fixed configuration shines on the screen. As a result, in that invention the flapping of the bird's wings ceases, thus indicating that the target object has been hit. One problem with that invention, however, is the fact that there is no way of indicating that the target has been hit other than by stopping the movement of the entire configuration.
Another problem with the prior art invention is that in these inventions the target rays projected onto the screen are emitted from a light source and are condensed by a condensing lens system or a condensing mirror system. The rays then pass through a silhouette plate or diaphragm, a condensing or projecting lens, and are finally reflected by a mirror to project the luminous target mark onto a screen. The hit rays from the light-emission gun reflect from the screen and are reflected by the mirror and focused onto a photoelectric element by a focusing lens.
In the above described prior art amusement machines, the condensing or projecting lens for the target rays is separate and independent of the focusing lens for the hit ray. When the distance from the lens to the screen is short, the target rays are not parallel to the hit rays at the same point on the screen. That is, the optical axis of the target rays emitted from the light source to the condensing lens is not parallel to the optical axis of the hit rays from the focus lens to the photoelectric element. Therefore, both the projecting lenses and the focusing lenses must be mounted in the housing so that the optical axis of the target rays and hit rays are at a specifically defined angle. Such a construction is very complicated.
As an example of the difficulity with this dual lens system, suppose a screen and unit are arranged at a specified distance from each other. The unit is made up of a light source, the photoelectric element and the lenses and has a means for emitting target rays and detecting hit rays which reflect from the screen. The angle between the optical axis of the target rays and the optical axis of the hit rays is set so as to correspond to the given distance conditions. When the unit is subsequently moved or the distance between the screen and the unit varied, or if the unit is inclined in a vertical or horizontal direction, or if the angle of inclination of the mirror within the unit is changed, a slip occurs between the center point of the range of the hit rays on the screen and the center point of the luminous mark on the screen. Accordingly, when the target mark on the screen is hit by the hit rays, because of the change in position of the unit, the quantity of light incident upon the focusing lens and the photoelectric element at the time of hitting will vary from the original amount which was designed for the first specified conditions. Thus, the sensitivity of the photoelectric elements varies and the hitting rate will vary with the location of the mark on the screen in these units which have separate and distinct projecting and focusing lens system.